Implemented DeflateBuffer

zlib.cpp

@@ -72,7 +72,77 @@ Handle<Value> InflateBuffer(const Arguments &args) {
 }
 
 Handle<Value> DeflateBuffer(const Arguments &args) {
-	return Undefined();
+	if (args.Length() != 1 && args.Length() != 2) {
+		return ThrowException(Exception::TypeError(String::New("zlib.deflateBuffer expects 1 or 2 arguments")));
+	}
+
+	if (!Buffer::HasInstance(args[0])) {
+		return ThrowException(Exception::TypeError(String::New("zlib.inflateBuffer expects a Buffer")));
+	}
+
+	int level = 6;
+	if (args.Length() == 2) {
+		if (!args[1]->IsNumber()) {
+			return ThrowException(Exception::TypeError(String::New("zlib.deflateBuffer expects arg 2 to be a number")));
+		}
+
+		level = args[1]->ToNumber()->Value();
+
+		if (level < -1 || level > 9) {
+			return ThrowException(Exception::TypeError(String::New("zlib.deflateBuffer expects arg 2 to be in -1..9")));
+		}
+	}
+
+	z_stream strm;
+	strm.zalloc = Z_NULL;
+	strm.zfree = Z_NULL;
+	strm.opaque = Z_NULL;
+	strm.avail_in = 0;
+	strm.next_in = 0;
+
+	if (Z_OK != deflateInit(&strm, level)) {
+		return ThrowException(String::New("deflateInit failed"));
+	}
+
+	const size_t CHUNK = 4096;
+	unsigned char out[CHUNK];
+
+	size_t outBufLen = CHUNK, outBufUsed = 0;
+	unsigned char *outBuf = new unsigned char[CHUNK];
+
+	strm.avail_in = BufferLength(args[0]->ToObject());
+	strm.next_in = (unsigned char*) BufferData(args[0]->ToObject());
+
+	do {
+		strm.avail_out = CHUNK;
+		strm.next_out = out;
+
+		if (Z_STREAM_END != inflate(&strm, Z_NO_FLUSH)) {
+			deflateEnd(&strm);
+			delete[] outBuf;
+			return ThrowException(String::New("deflate failed"));
+		}
+
+		size_t have = CHUNK - strm.avail_out;
+
+		if (have + outBufUsed > outBufLen) {
+			outBufLen *= 2;
+
+			unsigned char *newBuf = new unsigned char[outBufLen];
+			memcpy(newBuf, outBuf, outBufUsed);
+
+			delete[] outBuf;
+			outBuf = newBuf;
+		}
+
+		memcpy(outBuf + outBufUsed, out, have);
+		outBufUsed += have;
+	}
+	while (strm.avail_out == 0);
+
+	deflateEnd(&strm);
+
+	return Buffer::New((char*)outBuf, outBufUsed)->handle_;
 }
 
 extern "C" void init(Handle<Object> target) {